Best DSLR for black and white

In most (maybe all) cases, you can get better B&W pictures by taking color pictures and turning them to B&W in the digital darkroom, than you can by using a B&W mode on the camera. Therefore, I would not choose a DSLR based on some supposed advantage with its built-in B&W options. I would just get the DSLR that seems best to you, given your existing lens collection (if any), uses (about which we know nothing), and budget (is the $1k just for the body, or do you expect to get one or more lenses with that?).

There are a ton of threads (mostly in the Digital Darkroom forum) about techniques and specialized software for converting color to B&W. Indeed, there are whole books on the subject. And of course how you print is a significant issue too.

Black and white results are more specific to your post-processing skills than what camera you use. (BTW, my own experience is that this is also more true when using film.) You need to learn how to take a digital file and get the kind of black and white you want with the tools that work best for you. I happen to use Silver Efex Pro, which I find more intuitive, more versatile and more feature-rich than any techniques using only the Adobe tools. I can't think of a single digital camera characteristic other than noise (if you shoot at higher ISO) that will show a significant difference between cameras with converted black and white.

I have several manual focus Nikkors and manual Pentax Takumars, both super and auto. I would be using the camera for some landscape, some still life, and some street photography. I'd say about half the time, I would be creating slide shows for my living room TV, and half for printing; I would be having my printing done by a print shop.

B&W, in the digital capture world, is a rendering process. Pick a camera that is compatible with the lenses you like or want, then learn now to make great B&W photographs with them.

Most people will recommend shooting in color and converting to B&W in post-processing. I've found the D300 Nikon has an excellent B&W mode allowing for a complete range of simulated filters effects, toning to various degrees in a range of colors, and contrast and sharpness control. It's at least as good as B&W film (this will start arguments). Another advantage in shooting in the camera's B&W mode is that it gets you thinking in B&W and the instant review is in B&W.

... Another advantage in shooting in the camera's B&W mode is that it gets you thinking in B&W and the instant review is in B&W.

lol ... I have been shooting B&W for so many years that switching my camera to B&W in the JPEG output and getting a B&W viewfinder image is just too disturbing and strange.

I'm used to seeing color and letting my mind interpret B&W from it.

I knew when I wrote that line Godfrey would have a comeback, I love it!

So you wouldn't recommend something like a Fuji Finepix S3 or S5 Pro, which I understand has a larger dynamic range? I must admit, I'm not sure if that translates into a larger tonal palette.

Several points, going in chronological order:

I have several manual focus Nikkors and manual Pentax Takumars, both super and auto.

The good news is that both Nikon and Pentax have preserved at least basic functionality with old manual focus lenses even in their latest DSLR's (with of course the 1.53x "crop factor" with the ones in your price range--do you have a lens that will be wide enough on the cameras we're talking about?). The bad news is that, especially with the less expensive Nikon bodies, you can have metering headaches and the like. Also, really old lenses may not be up to the resolution demands (14 MP on on "APS-C" sensor is 97 lp/mm) or need for flare resistance (the sensors reflect and scatter a lot more light than film does) of a DSLR.

I would be using the camera for some landscape, some still life, and some street photography.

That fairly diverse set of uses doesn't scream for any particular DSLR. Given you budget and lenses, I'd probably get a Nikon D90 ($810 for the body only). If you need a wider lens than your current ones, and want a zoom lens, I'd look hard at the new Tamron 17-50mm f/2.8 VC ($625 after rebate), which would give you optical image stabilizations and a range roughly equivalent to a 26-77mm lens on a 35mm camera, with a constant maximum aperture of f/2.8. If you decide you need a lens but don't want to spend the $1435, I'd downgrade the body to a D5000 ($616) if that Tamron lens has a built-in focus motor (check!) for a total price of $1241.

I've found the D300 Nikon has an excellent B&W mode allowing for a complete range of simulated filters effects, toning to various degrees in a range of colors, and contrast and sharpness control.

That may be. And it might prove entirely satisfactory for many people. But it is beyond intelligent dispute that starting with a full color raw data file gives you the most ability to get the results you want--and the ability to get very different, but quite possible better, results years from now. Of course, if the camera lets you capture both a doctored-up JPEG and an unadulterated raw file, that may be the best of both worlds.

So you wouldn't recommend something like a Fuji Finepix S3 or S5 Pro, which I understand has a larger dynamic range? I must admit, I'm not sure if that translates into a larger tonal palette.

Well a lot of people use dynamic range at best ambiguously, which is an old problem. We really need to break it down into input dyanmic range--the ability of the camera to capture detail in both very bright and very dark areas--and output dynamic range, the ability of the final output medium to show a wide range of dark-to-light. The best regular DSLR's, with appropriate exposure controls and digital darkroom work, can capture detail about four stops brighter, and five stops darker, than middle-tone (see, e.g., http://www.dpreview.com/reviews/nikond5000/page18.asp). That can be an important issue, but unless you subjects have a brightness range that exceeds that the camera can capture, it's not an issue. Of course, especially for B&W, you usually want to adjust (typically, maximize) the output dynamic range so that you have significant amounds of the darkest and lightest tones with the desired midtone contrast. But assuming basically correct exposure, that's for the digital darkroom and tools like curves (or even levels). Some printing techniques can produce a considerably wider range of dark-to-light than others. Mpix can produces nice, inexpensive ($3 for an 8x10) prints on Ilford real B&W, silver-halide paper (albeit RC, and limited to the "pearl" semi-matte surface). For big money ($40+ for an 8x10, there are places that will print you files onto real FB silver-halide paper. And of course there are injets and a variety of inkjet-like processes, some of which can produce quite nice results.